Mongoose’s modernization of the classic Traveller science fiction RPG is a fine example of a mature gaming system. It has maintained (and in some cases improved upon) some of Marc Miller’s great innovations, like the random and detailed character generation system and a simple but effective skill system.

We’ve played a lot of Mongoose Traveller (MGT) over the last year or so, and a few of us have mused that, because of MGT’s high tech level, the system’s skill and equipment lists could be scaled down or modified to play other genres.

We weren’t the only ones thinking that. The folks at Mongoose Publishing, it turns out were busily working on an Old West adaptation of the MGT system, Cowboys vs. Xenomorphs.

Cowboys vs. Xenomorphs is a setting book disguised as an adventure. The first chapter provides a fairly extensive list of genre- and period-appropriate equipment, including clothing, vehicles and two pages of weapons — and yes, and entire page of revolvers.

The second chapter details the small boomtown of Bent River, including details of the various businesses and an extensive list of NPCs.

The next three chapters detail the adventure itself, including events that don’t involve aliens. The town of Bent River has enough detail in it to run an entire mini campaign just on the potential intrigue there. The alien menace has its own chapter, detailing events and locations that will be familiar to those who’ve watched any classic science fiction films.

The back of the book has the “Main Cast,” that is pregenerated PCs for the game. This is where I started to get a bit disappointed. I was hoping for a chapter with common professions, so players could make their own old west characters. Alas, it wasn’t there.

They do include one career, Desperado, which is presented in the long-form, like those found in the splat books. One could use this as a guide to homebrew additional careers, like trollop, miner, town drunk, lawman, cowpoke, school marm, etc. Personally, I would rather they devoted the pages of pregens to the normal two-page careers, like those found in the core book.

In spite of this misstep, I do feel that Cowboys vs. Xenomorphs would make a great addition to one’s MGT collection.